Metallized dyes derived from hydroquinone mono-ethers



METALLHZED EYES DERIVED FROM HYDRO- QUINONE MON-ETHERS Joseph Seruto, Merideu, Conan, assignor to American Cyanamid (Iornpany, New York, N. Y., a corporation of Maine No Drawing. Application June 17, 1949, Serial No. 99,864

16 \Claims. (Cl. 260-449) This invention relates to a new series of metallized monazo dyes.

Monazo dyes are among the cheapest dyestuffs which can be prepared, but they suffer from a limited color range; comparatively few are available in black, green or blue shades, and most of these few require unsual and roundabout processes involving expensive and uncommon diazo or coupling components. The others show inferior dyeing or fastness properties. As a result, most of the good black, green, or blue dyes are polyazo dyes and, in general, they are more expensive than the monazo dyes which can be used for the other color shades.

The metallized monazo dyes of the present invention have the unusual properties of giving blue, black, or green shades when prepared from many common diazo components and show excellent dyeing characteristics and light fastness. A good method of preparation consists in metallizing the dyes obtained by coupling diazo components with monoethers of hydroquinone and to have the following general formula:

A1--N=N- in which R is the hydrocarbon radical of the ether and Ar is a sulfonated aromatic radical substituted ortho to the azo linkage by a lake-forming group such as hydroxyl, methoxyl, carboxyl or halogen. The diazo component should be free from lake-forming units other than the azo linkage and the groups ortho thereto, because such lake-forming units, for example, the salicylic acid structure, result in the partial or total formation of lakes which do not involve the azo linkage and which are very inferior dyestufis. Consequently, the present invention does not include metallized dyes from these practically useless products.

The valuable properties of the metallized azo dyestuiis of the present invention are obtained when azo dyes are metallized which are prepared from any hydroquinone monoether and are not limited to those produced from one or two particular ethers. Thus, for example, in the general formula R may be any alkyl group of which methyl, ethyl, butyl and amyl are typical, or it may be an alkylene radical such as allyl. Aromatic ethers, in which R is an aryl radical such as phenyl, tolyl, or thymyl, are also included, as well as are aralkyl ethers where R may, for example, be benzyl, phenethyl, 'y-phenylpropyl, and the like.

Almost any of the usual diazo components may be used so long as they have a lake-forming group ortho to the diazo and are free from other lake-forming structural units. It is an advantage that excellent metallized dyes may be prepared from some of the simplest diazo components, such as 1-amino-2-naphthol-4-sulfonic acid,

Patent 2,709,597 Patented May 311, 1955 ice 2 4-nitro-2-aminophenol-6-sulfonic acid, and its isomer 6-nitro-2-aminopl1enol-4-sulfonic acid. Diazo compounds from the first two amines give blue and green dyes respectively, While those from the last give black. Diazo compounds may be used derived from other typical amines such as 4-sulfoanthranilic acid, S-sulfoanthranilic acid, 2 aminophenol 4 sulfonic acid, 2 arnino-4-chlorophenol-5-sulfonic acid, 2-amino-4-chlorophenol-6-sulfonic acid, 2-amino-6-nitroanisole-4-sulfonic acid, and 1-amino-6-nitro-2-naphthol-4-sulfonic acid.

Diazo compounds from heterocyclic amines may also be used to couple with the hydroquinone monoethers. Typical amines are 5-amino-6-hydroxyquinoline-8-sulfonic acid, l-(p-sulfophenyl)-3-methyl-4-amino5-pyrazolone, or 2-(4-amino-3-methoxyphenyl)-6-methylben- Zothiazolesulfonic acid.

While it is one of the most important advantages of the present invention that it is possible to produce valuaole blue, green and black metallized azo dyes from common diazo components, it should be understood that the invention is not intended to be limited to metallized dyes of these colors. It is possible also to produce other shades such as grays, bordeaux and the like and these metallized dyestuflfs are also included even though they are not as unique as the green, blue and black dyes. It is an advantage of the present invention that metallization proceeds smoothly and that no new or difficult metallization procedures are required. The common metallizing metals, such. as chromium, copper, cobalt, iron and the like, may be introduced into the dyestufis in the form of complexes by refluxing an aqueous solution of the dyestult with salts or other suitable compounds of the metallizing metals. The particular anion in the metal salt solution is not important so long as the acid is not one that tends to react with the dyestuif, and common salts such as chlorides, sulfates, acetates and the like may be used. In some cases other compounds which are not salts may be employed. In the case of chromium complexes the acetate is the most common salt used and is preferred. Any other of the ordinary metal salts may be substituted.

It is not intended to limit the present invention to any particular method of preparing a metallized azo dyestufi. In general, however, I have found that coupling proceeds best on the alkaline side, typical reaction media being strong sodium hydroxide solutions (35-40%), aqueous alkaline pyridine solutions and the like.

The invention will be described in greater detail in conjunction with the following specific examples. Parts are by weight.

Example 1 (RH on Hs0@ -N N N02 it on,

A solution of 23 parts of 2-amino-4-nitrophenol-6-sulfonic acid in 130 parts of 10% sodium carbonate is treated with 35 parts of concentrated hydrochloric acid and parts of ice and diazotized in the usual way with 5N sodium nitrite solution. Excess acidity is then destroyed with sodium bicarbonate and the diazo is added to a solution of 17 parts p-methoxyphenol in 100 parts of water, parts of pyridine, and 29 parts of 5N sodium hydroxide. After thorough stirring, the mixture is allowed to stand five minutes and diluted with parts of water. One hour later it is added to 5900 parts of water, stirred to complete solution, and then neutralized. The product is filtered and dried at 60 C. When dyed on aroaear wool by the top chrome method it produces dark green shades with excellent light fastness.

The chromium acetate solution used in metallizations in these examples is prepared as follows: 136 parts of chromic acid is dissolved in 1156 parts of water. To the solution is added 163 parts of glacial acetic acid and 50 parts of glucose. The solution is slowly heated to the boil and gently boiled until the chromic acid is completely reduced. After cooling, the solution is diluted to the volume of 2000 parts of water.

Metallization is carried out by refluxing 2 parts of the above prepared dyesuif overnight in parts of water and 12 parts of the above prepared chromic acetate solution. The solution is cooled, treated with 6 parts of concentrated hydrochloric acid, and filtered. The product is washed with acetone and dried. It gives green shades on Wool.

Example 2 SOaH OCHa A solution of 50 parts of 6-nitro-2-aminophenoll-sulfonic acid in 280 parts of 10% sodium carbonate solution is acidified With 72 parts of concentrated hydrochloric acid, treated with 200 parts of ice, and diazotized with 5N sodium nitrite. The diazo solution is then added to a solution of parts of 4-methoxyphenol and 71 parts of 5N sodium hydroxide in 200 parts of water and 240 parts of pyridine. After stirring for fifteen minutes the crystalline product is filtered and dried at 60 C. It gives gray to black chrome dyeings.

Two parts of the dyestuff thus prepared are metallized by refluxing in 100 parts of Water, 120 parts chromic acetate solution (prepared as described in Example 1), and 11 parts 5N sulfuric acid. When metallization is complete the product is salted out with 500 parts of sodium chloride, filtered, and dried. It gives black dyeings of excellent fastness.

Example 3 OCHs A paste of 80 parts of 4-methoxyphenol and 760 parts of sodium hydroxide is diluted with 300 parts of water and treated at 4550 with 165 parts of the diazo oxide of 1-amino-Z-naphthol-4-sulfonic acid. After one hours stirring at 40, the mixture is cooled to room temperature and treated with 500 parts of ice and 1350 parts of concentrated hydrochloric acid. The product is filtered, dried, washed with benzene and then with concentrated sodium bicarbonate, and then dried at C. It gives navy blue chrome dyeings of good fastness and may be metallized according to the procedure described in Example 1.

Example 4 on on Fifty parts of 2-amino-4-nitrophenol-6-sulfonic acid are dissolved in 280 parts of 10% sodium carbonate solution, acidified with 130 parts of concentrated hydrochloric acid, cooled by the addition of 150 parts of ice, and diazotized. The diazo solution is buffered with sodium bicarbonate solution and added to a solution of 35 parts of p-ethoxyphenol in parts of Water, 70 parts of 5N sodium hydroxide, and parts of pyridine. After a short period of stirring, the crystalline product is filtered.

The unmetallized dye dyes wool a reddish-brown shade which is converted to green and violet shades respectively by after-treatment with salts of chromium and copper. After-treatment with salts of cobalt, iron or nickel gives attractive brown shades.

Metallization of the dye with chromium acetate, as described in Example 1, gives a green dyestuif of excellent fastness. Metallization with other metals may also be accomplished by refluxing the dye with a salt of the desired metal. In this way copper, cobalt, iron and nickel complexes can be prepared. These complexes, when used to dye wool give shades comparable with those obtained as described above by after-treatment of the unmetallized dye on the fiber.

Example 5 To a vigorously stirred paste of 9 parts of p-ethoxyphenol 76 parts of 50% sodium hydroxide solution, and 20 parts of water, is added 18 parts of the diazo oxide of 1-amino2-napthol-4-sulfonic acid. After six hours stirring at 30-35 the mixture is treated with approximately its own weight of ice and acidified with parts of concentrated hydrochloric acid. The product is filtered and dried at 60. It gives navy blue chrome dyeings, and can be metallized by refluxing in water and chromic acetate according to the general procedure of Example 1. The chromium complex is a blue dyestuff of excellent fastness and dyeing properties.

Twenty parts of diazotized l-(p-sulfophenyl)-3-methyl- 4-amino-5-pyrazolone and 16 parts of p-ethoxyphenol are made into a paste with parts of 50% sodium hydroxide. Solution is completed by stirring and slowly adding 200 parts of water. Stirring is continued for one hour at room temperature. The solution is then acidified to pH 3 with the aid of concentrated hydrochloric acid and the product filtered and dried at 60. Metallization is accomplished by refluxing 15 parts of the dyestuff in 100 parts of water and 50 parts of chromic acetate solution prepared as described in Example 1. After three hours of refluxing, 13 parts of 5N sulfuric acid is added and refiuxing continued two hours longer. The product is filtered, washed, and dried. It gives Bordeaux dyeings of excellent properties.

Example 7 11 (n1 2-aminol-nitrophenol-6-sulfonic acid is diazotized and coupled with p-butoxyphenol, according to the procedure of Example 1. The resulting dyestufl? gives olive green shades of excellent fastness, when dyed on Wool by the top chrome method. Metallization with chromic acetate gives the chromium complex, which is a valuable dye for producing dark green shades.

Example 8 S 0311 O 04H!) Fifty parts of 6-nitro-2-aminophenol-4-sulfonic acid is diazotized and coupled with 37 parts of p-butoxyphenol in sodium hydroxide-pyridine solution, according to the procedure of Example 1 and subsequent examples. The product gives black chrome dyeings. Metallization is effected in boiling chromic acetate solution at pH 2.7. The product is a black dyestuff of good all-round properties.

Example 9 OC-tHli p-Butoxyphenol is coupled with diazotised l-amino-2- naphthol-4-sulfonic acid in concentrated sodium hydroxide, according to the procedure of Example 5. The product gives navy blue dyeings by the top chrome method. The chromated dyestuli also gives blue dyeings.

Example 10 (.FH (|)H 4-IlllfO-2-"tmillOPhCl'lOl-6-Slllf0l1l acid is diazotized and coupled with pbenzyloxyphenol in pyridine-aqueous sodium hydroxide medium according to the procedure described in Example 1. The product gives green chrome dyeings. it may be metallized by the procedure described in the above examples.

Example 11 on OH N o -N=NQ SOzH 0011205115 Six parts of 6-nitro-2-aminophenol-4-sulfonic acid are diazotized and coupled with 4 parts of p-benzyloxyphenol. The dye is metallized in the usual manner with chromium acetate and gives valuable black dyeings.

Example 12 OH ?H HSOr@-N=N- CH2C6H5 Diazotized l-amino-2-naphthol-4-sulfonic acid is coupled with p-benzyloxyphenol according to the general procedure of Example 3. The product gives blue dyeings of good fastness by the top chrome method. The chromium complex, which is prepared by the usual method as de- 5 scribed in above examples, also gives blue dyeings.

in which R is a hydrocarbon radical having not more than 10 carbon atoms and Ar is a mono-sulfonated aromatic radical containing not more than two rings and 20 having a single complex lake-forming group ortho to the azo linkage.

2. A metal complex of a dyestuff having the following formula:

OH on l in which R is an aliphatic hydrocarbon radical having not more than 10 carbon atoms.

3. A metallized dycstufi according to claim 2 in which R is an alkyl radical.

4. A dycstuff according to claim 3 in which the alkyl radical is ethyl.

5. A metallized dyestufl having the formula:

in which R is a hydrocarbon radical having not more than 10 carbon atoms.

6. A dyestulf according to claim 5 in which R is alkyl. 7. A metallized dyestuif having the formula:

(III-I (|)H HSOa- N=N in which R is a hydrocarbon radical having not more than 10 carbon atoms.

8. A metallized dyestutf having the formula:

in which R is an aliphatic hydrocarbon. radical having 0 not more than 10 carbon atoms.

9. A dyestuff according to claim 8 in which R is alkyl. 10. A metallized dyestufi according to claim 1 in which the metal is chromium.

11. A metallized dyestufl' according to claim 2 in which the metal is chromium.

12. A metallized dyestuff according to claim 4 in which the metal is chromium.

13. A metallizcd dyestuif according to claim 5 in which the metal is chromium.

14. A metallized dyestufi according to claim 7 in which the metal is chromium.

15. A metal complex of a monoazo dyestuff of the formula OH OH azo-linkage in the ortho position to the hydr'oxy group thereof.

16. A metallizcd dyestuif according to claim 15 in which the metal is chromium.

References Qited in the file of this patent UNITED STATES PATENTS 1,011,770 Geldermann Dec. 12, 1911 1,867,083 Krzikalla et al July 12, 1932 1,947,945 Lange Feb. 20, 1934 2,008,602 Strauo et al July 16, 1935 2,191,040 McNally Feb. 20, 1940 2,495,244 Felix et al. Jan. 24, 1950 2,599,147 Widmer et al. 2. June 3, 1952 FOREIGN PATENTS 73 Great Britain of 1911 

1. A METAL COMPLEX OF A MONOAZO DYESTUFF OF THE STRUCTURE 